Old weld symbol 2

[TehMightyEngineer]

This is a new one for me. In the attached welding detail from a 1957 era drawing they show two details for various thicknesses. The only difference is one weld all around symbol has a dot in the middle. What does this dot mean?

Maine EIT, Civil/Structural.

 

[hawkaz]

I have not seen this before either- but based on the thicknesses- I would guess that the dot indicates pre-heat

 

[TehMightyEngineer]

Mmmm, that could be it. It's all A36 grade steel.

Maine EIT, Civil/Structural.

 

[topsisu]

If you look in the 7th Ed (blue) AISC Steel Manual you will see t6he solid dot is the old Field Weld symbol.

 

[msquared48]

topsisu has it. The flag replaced the dot for field welding in the 80's.

Mike McCann, PE, SE (WA)

 

[Hokie93]

The 4th and 5th edition AISC Steel Construction Manuals use a solid circle to indicate a field weld. That is, the circle that today indicates an "all around" weld is filled in solid. The 5th edition AISC steel manual was in effect from the late 1940's to the early 1960's so it would cover the timeframe of your drawing. Note, however, that a solid circle is not the same as the notation you have shown (circle with a dot). Perhaps the drafter was just saving some lead or the symbol may mean something entirely different. If you really need to know, you might try contacting AISC or Lincoln Electric.

 

[dhengr]

TehMightyEngineer:
The open circle meant weld all around. The solid dot meant field weld. We couldn’t afford so many flags in the olden days, Bettsy Ross still held the patent on the flag at that time.

 

[Archie264]

I'm trying to figure out why a thicker plate would require a field weld... Maybe the plate corresponds to a size of column that was too large for some fabrication shops? Just grasping a straws here...

 

[KootK]

Let's hear it for the flag. The dot seems as though it would be plan reading / reproduction nightmare.

The greatest trick that bond stress ever pulled was convincing the world it didn't exist.

 

[TehMightyEngineer]

Thanks guys, always love the wealth of knowledge on here.

Maine EIT, Civil/Structural.

 

[paddingtongreen]

The field weld on the thicker plate surprises me too.

I don't remember any problem seeing the dot.

What does surprise me is that the shop welds are all round, this means they have to flip the column or weld overhand. I expect to see weld on the outside of one flange, on the inside of the other flange and one or both sides of the web. Of course, moment connections are different, they may justify the extra work.

Michael.
"Science adjusts its views based on what's observed. Faith is the denial of observation so that belief can be preserved." ~ Tim Minchin

 

[msquared48]

I think the thicker plate field welding issue is not required stipulation, but one that is allowed. Possibly the thinner plates needed to be preheated in the shop, but not the thicker ones.

Mike McCann, PE, SE (WA)

 

[JedClampett]

This makes me feel old. When I started as a young structural engineer, that was the field weld symbol. Everyone knew it. Now it's fading into the antique bin. The younger engineers don't even recognize it.
Next they'll come up with a contraption to replace slide rules.

 

[msquared48]

Or engineers...

Mike McCann, PE, SE (WA)

 

[msquared48]

From my 1967 Textbook "Steel Design Manual" by McCormac:

Mike McCann, PE, SE (WA)

 

[BUGGAR]

Those of you that have a little age on them can remember cigarette ash burns being confused for the field weld dot (my drawings were riddled with cig burns). Interestingly, when the fabricator called, he immediately understood.

 

[JC]

The twelfth edition of "The Procedure Handbook of Arc Welding" June 1973 shows a field weld flag symbol. It appears that the symbol was changed around 1970.